Method of initializing and establishing links in a multi-mode mobile terminal

ABSTRACT

A method of performing a handover with at least one of a homogeneous and heterogeneous network is disclosed. More specifically, the method comprises establishing a heterogeneous network handover module for converging information from the at least one network interface module associated with the at least one of a homogeneous and heterogeneous network into a unified presentation and receiving a message for powering on at least one network interface module in a mobile terminal from the heterogeneous network handover module. The method further comprises performing a power on operation for activating the at least one network interface module and transmitting a confirmation message for indicating a power on operation status to the heterogeneous network handover module.

This application claims the benefit of Korean Application No.10-2005-0030122, filed on Apr. 11, 2005, which is hereby incorporated byreference.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a method of initializing andestablishing links, and more particularly, to a method of initializingand establishing links in a multi-mode mobile terminal.

2. Discussion of the Related Art

FIG. 1 is a diagram showing a Protocol Stack Architecture according toIEEE 802.16. As shown in FIG. 1, conversion or mapping of the data,received from the outside communication network via the CS ServiceAccess Point (SAP), to MAC Service Data Unit (SDU), received by a MACCommon Part Sublayer (CPS) via the MAC SAP can take place at aService-Specific Convergence Sublayer (CS). Here, the SDUs of theoutside communication network are classified and assigned tocorresponding MAC Service Flow Identifier (SFID) or ConnectionIdentifier (CID). For a diverse protocol interface, provisions relatedto a multiple CS are provided. The internal format of the CS payload isconsidered a unique characteristic of the CS. Moreover, the MAC CPS isnot required to analyze or comprehend the format of any informationreceived after the CS payload.

The MAC CPS provides features such as system access, allocation ofbroadband width, establishing access, and access management. Moreover,the MAC CPS receives data, classified by a specific MAC access method,from various CS via the MAC SAP. Furthermore, the data is transmittedthrough the PHY layer while Quality of Service (QoS) is applied to thescheduling feature.

The PHY control and statistical data from between the MAC CPS and thePHY is transmitted via the PHY SAP. In the definition of the PHY, thereare various provisions and is appropriate in each specific frequencyrange and application.

FIG. 2 illustrates the protocol stack architecture of IEEE 802.11, andFIG. 3 illustrates the protocol stack architecture of 3^(rd) GenerationPartnership Project (3GPP).

In IEEE 802.21, discussions are under way to establish an internationalstandard for a Media Independent Handover (MIH) between heterogeneousnetworks. One of the objects of the international standard is to provideseamless handover and service continuity to enhance user experience ofmobile devices. As a basic requirement, there are a MIH function, anevent trigger, a Command Service (CS) and an Information Service (IS).

A mobile terminal is a multi modal which supports at least one interfacetype, and the interface types can be any one of the following. Theinterface types include a wire-line type similar an Ethernet of IEEE802.3, a wireless interfaces based on IEEE 802.xx (e.g., 802.11, 802.15,802.16), and an interface defined by a cellular standard organization(e.g., 3^(rd) Generation Partnership Program (3GPP), 3^(rd) GenerationPartnership Program 2 (3GPP2)).

The MIH is defined between the IEEE 802 series interfaces or between theIEEE802 series interfaces and non-IEEE 802 series interfaces (e.g.,3GPP, 3GPP2). Furthermore, the MIH has to be supported by upper layermobile support protocol such as a Mobile Internet Protocol (Mobile IP)and a Session Initiation Protocol (SIP) in order to provide seamlesshandover and uninterrupted service.

FIG. 4 illustrates a general MIH reference model used to support MIHfunction. The SAP for supporting the MIH function is as follows.

MIH_MGMT_SAP defines the interface between the MIH function stack andthe management plane. MIH_MGMT_SAP can be used to send the MIH messagesto peer MIH entities. The messages near the management frame can be sentwithout authentication. MIH_MGMT_SAP indicates the primitives used byMedia Independent Event Services, Media Independent Command Services,and Media Independent Information Services.

MIH_SME_SAP defines the interface between the MIH function stack and aStation Management Entity (SME) of IEEE 802.11 or between MIH functionstack and a Network Control and Management System (NCMS) of IEEE 802.16.Furthermore, MIH_SME_SAP can be same as MIH_MGMT_SAP.

MIH_USER_SAP defines the interfaces for communicating with the layersabove the upper layers (e.g., IP layer-Layer 3).

MIH_MAC_SAP defines the interface between the MIH and the MAC of otherinterfaces. The other interfaces include, for example, IEEE 802.11, IEEE802.16, 3GPP, and 3GPP2. The interfaces indicated by MIH_MAC_SAP areused to transmit between peer entities. Here, no new interfaces andprimitives need to be defined for MIH_MAC_SAP. However, the interfacesindicated by MIN_MAC_SAP can be used by the peer MIH entities totransmit the payloads near the MIH protocol.

MIH_PHY_SAP defines the interface between the MIH and the PHY layer ofother interfaces (e.g., IEEE 802.11, IEEE 802.16, 3GPP, and 3GPP2).Here, the MIH uses the MACs of the corresponding interface tocommunicate via the PHY of the corresponding interface. There is no needto define new interfaces or primitives for MIH_PHY_SAP.

A Layer SAP (LSAP) defines the interface between the MIH and a LowerLink Control (LLC) of other interfaces. The MIH establishes connectionand communicates with the peer LLC entities. Thereafter, the MIH usesthe LLC interface directly to establish data path for transmitting MSDUsvia other links. Here, there is no need to define new interfaces orprimitives for LSAP.

MIH_RRC_SAP defines the interface between the MIH function and theinterfaces between a Radio Resource Control (RRC) of other interfaces.

The MIH function is placed below the IP layer. The MIH functionfacilitates the handover handling process by using the input values fromLayer 2 such as trigger event information and information of othernetworks. Moreover, the MIH Function can include input values (e.g.,user policy and configuration) which can affect the handover procedure.In addition, general interfaces (e.g., the Mobile IP and the SIP) aredefined between Layer 3 entities and the MIH Function. These interfacesprovide information associated with Layer 1 (i.e., PHY Layer) and Layer2 (i.e., MAC Layer) as well as mobility management. The MIH acquiresinformation on lower layer and the network with the aid of the ES andthe IS.

Furthermore, in the upper layer, the mobile terminal should include theMIH function for monitoring and controlling the status of other links.FIG. 5 illustrates a mobile terminal having the MIH function and afunctional entity and transmission protocol of a network. In FIG. 5, thedotted lines represent services such as a primitive and the eventtrigger.

FIG. 6 illustrates a configuration of an IEEE 802.16 system in aprotocol stack considering the MIH. This model can be applied to boththe mobile terminal and the network. However, because a multi-modemobile subscriber station and a multi-stack mobile subscriber stationshould be taken into consideration, a mobile subscriber station shouldinclude the configuration shown in FIG. 6.

FIG. 7 illustrates a configuration of an IEEE 802.11 system in aprotocol stack considering the MIH. This model can be applied to boththe mobile terminal and the network. However, because a multi-stackmobile subscriber station of multi-mode should be taken intoconsideration, a mobile subscriber station should include theconfiguration shown in FIG. 7.

FIG. 8 illustrates a configuration of a 3GPP system in a protocol stackconsidering the MIH. This model can be applied to both the mobileterminal and the network. However, because a multi-stack mobilesubscriber station of multi-mode should be taken into consideration, amobile subscriber station should include the configuration shown in FIG.8.

According to the conventional art, there is no way to initialize andestablish control link in a multi-mode mobile terminal having at leasttwo interface types associated with the wired or wireless schemes. Inparticular, if placed in the MIH stack, there is no way to establishlink for operating the mobile terminal and accessing the network and tocontrol each interface of the multi-mode mobile terminal. As such, thereare delays in operating the mobile terminal and accessing the network.Moreover, since power of the multi-mode mobile terminal could not bemanaged, power consumption by the multi-mode mobile terminal wasexcessive.

SUMMARY OF THE INVENTION

Accordingly, the present invention is directed to a method ofinitializing and establishing links in a multi-mode mobile terminal thatsubstantially obviates one or more problems due to limitations anddisadvantages of the related art.

An object of the present invention is to provide a method of performinga handover with at least one of a homogeneous and heterogeneous network.

Additional advantages, objects, and features of the invention will beset forth in part in the description which follows and in part willbecome apparent to those having ordinary skill in the art uponexamination of the following or may be learned from practice of theinvention. The objectives and other advantages of the invention may berealized and attained by the structure particularly pointed out in thewritten description and claims hereof as well as the appended drawings.

To achieve these objects and other advantages and in accordance with thepurpose of the invention, as embodied and broadly described herein, amethod of performing a handover with at least one of a homogeneous andheterogeneous network includes establishing a heterogeneous networkhandover module for converging information from at least one networkinterface module associated with the at least one of a homogeneous andheterogeneous network into a unified presentation. The method furtherincludes receiving a message for powering on at least one networkinterface module in a mobile terminal from the heterogeneous networkhandover module, performing a power on operation for activating the atleast one network interface module, and transmitting a confirmationmessage for indicating a power on operation status to the heterogeneousnetwork handover module.

In another aspect of the present invention, a method of performinghandover with at least one of a homogeneous and heterogeneous networkincludes establishing a heterogeneous network handover module forconverging information from at least one network interface moduleassociated with the at least one of a homogeneous and heterogeneousnetwork into a unified presentation. The method further includesreceiving a message for powering down at least one network interfacemodule in a mobile terminal from the heterogeneous network handovermodule, performing powering down operation for deactivating the at leastone network interface module, and transmitting a confirmation messagefor indicating a power down operation status to the heterogeneousnetwork handover module.

Yet in another aspect of the present invention, a method of performing ahandover to at least one of a homogeneous and heterogeneous networkincludes establishing a heterogeneous network handover module forconverging information from at least one network interface moduleassociated with the at least one of a homogeneous and heterogeneousnetwork into a unified presentation. The method further includesreceiving a message for powering on at least one network interfacemodule in a mobile terminal from a management module, transmitting amessage for powering on the at least one network interface module in themobile terminal from the heterogeneous network handover module to the atleast one network interface module in a mobile terminal, and receiving aconfirmation message for indicating a power on operation status from theat least one network interface module.

In a further aspect of the present invention, a method of performing ahandover to at least one of a homogeneous and heterogeneous networkincludes establishing a heterogeneous network handover module forconverging information from at least one network interface moduleassociated with the at least one of a homogeneous and heterogeneousnetwork into a unified presentation. The method further includesreceiving a message for powering down at least one network interfacemodule in a mobile terminal from a management module, transmitting amessage for powering down the at least one network interface module inthe mobile terminal from the heterogeneous network handover module tothe at least one network interface module in a mobile terminal, andreceiving a confirmation message for indicating a power down operationstatus from the at least one network interface module.

In another aspect of the present invention, a method of performing ahandover to at least one of a homogeneous and heterogeneous networkincludes establishing a heterogeneous network handover module forconverging information from at least one network interface moduleassociated with the at least one of a homogeneous and heterogeneousnetwork into a unified presentation. The method further includesreceiving from a management module a command for establishing at leastone connection with at least one network interface module, performing aconnection establishment procedure by transmitting a setup message forestablishing the at least one connection to the at least one networkinterface module in a mobile terminal and receiving a result message forindicating a setup result from the at least one of the network interfacemodule, and transmitting a notification message for providing themanagement module with the results of the connection establishmentprocedure.

It is to be understood that both the foregoing general description andthe following detailed description of the present invention areexemplary and explanatory and are intended to provide furtherexplanation of the invention as claimed.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings, which are included to provide a furtherunderstanding of the invention and are incorporated in and constitute apart of this application, illustrate embodiment(s) of the invention andtogether with the description serve to explain the principle of theinvention. In the drawings;

FIG. 1 is a diagram showing a Protocol Stack Architecture according toIEEE 802.16;

FIG. 2 illustrates the protocol stack architecture of IEEE 802.11;

FIG. 3 illustrates the protocol stack architecture of 3^(rd) GenerationPartnership Project (3GPP);

FIG. 4 illustrates a general MIH reference model used to support MIHfunction;

FIG. 5 illustrates a mobile terminal having the MIH function and afunctional entity and transmission protocol of a network;

FIG. 6 illustrates a configuration of an IEEE 802.16 system in aprotocol stack considering the MIH;

FIG. 7 illustrates a configuration of an IEEE 802.11 system in aprotocol stack considering the MIH.

FIG. 8 illustrates an architecture of a 3GPP system in a protocol stackconsidering the MIH;

FIG. 9 illustrates an architecture for implementing a protocol stack ina multi-mode mobile terminal which does not include a MIH CS inaccordance with an embodiment of the present invention;

FIG. 10 illustrates an architecture for implementing a protocol stack ina multi-mode mobile terminal which includes an MIH CS in accordance withone embodiment of the present invention;

FIG. 11 illustrates an architecture for implementing a protocol stack ina multi-mode mobile terminal which includes an upper MIH CS and a lowerMIH CS in accordance with one embodiment of the present invention;

FIG. 12 illustrates an architecture for implementing a protocol stack ina multi-mode mobile terminal, wherein an MIH CS exists as a function inaccordance with one embodiment of the present invention;

FIG. 13 is a flowchart of a procedure for establishing initialconnection according to another embodiment of the present invention;

FIG. 14 is a flowchart of a procedure according to an embodiment of thepresent invention;

FIG. 15 is a flowchart of a procedure according to another embodiment ofthe present invention;

FIG. 16 is a flowchart of a procedure according to another embodiment ofthe present invention;

FIG. 17 is a flowchart of a procedure according to yet anotherembodiment of the present invention;

FIG. 18 is a flowchart of a procedure according to another embodiment ofthe present invention; and

FIG. 19 is a flowchart of a procedure according to another embodiment ofthe present invention.

DETAILED DESCRIPTION OF THE INVENTION

Reference will now be made in detail to the preferred embodiments of thepresent invention, examples of which are illustrated in the accompanyingdrawings. Wherever possible, the same reference numbers will be usedthroughout the drawings to refer to the same or like parts.

The present invention defines a service access point (SAP) to support amedia independent handover function (MIH). It may be classified by theexistence or non-existence of an MIH convergence sublayer (MIH CS)according to message distribution and an MIH function range. Theexistence of the MIH CS can be additionally divided into an MIH lowerconvergence sublayer and an MIH higher convergence sublayer. The MIH CSis configured across all interface types of a multi-stack provided to aterminal. The MIH CS deals with policy enforcement, network selection,QoS parameter mapping, handover signaling and the like. Preferably, theobject of the MIH CS is to act as a connection between a higher protocoland a lower MIH to facilitate equal application among differenttechnologies regardless of the technologies' features dependent onmedia. Preferably, the technologies comprise at least one of awired-line broadband system, a wireless broadband system and a cellularsystem. Preferably, the broadband system comprises at least one of awireless local area network and a wireless metropolitan area network.Preferably, the cellular system comprises at least one of WCDMA and acdma2000.

In the embodiments of the present invention, the term ‘linkestablishment’ and any variations thereof can be used interchangeablywith a term ‘link setup’ and its variations. In addition, a term‘entity’ can also be referred to as a ‘module.’ For example, amanagement entity can be referred to as a management module.

FIGS. 9-12 illustrate examples of protocol stacks to which a method ofinitializing and establishing link in a multi-mode mobile terminal canbe applied according to the present invention. The present invention canbe made available to support handover between heterogeneous networksincluding wired and wireless networks. In particular, the presentinvention relates to a multi-mode mobile terminal having at least twomultiple wired and/or wireless interface types (e.g., Ethernet, wirelessLAN, broadband radio access system, and cellular system).

A protocol stack of the multi-mode mobile terminal can be classifiedinto a MIH layer having a MIH Convergence Sublayer (CS) or not havingthe MIH CS. With that, FIG. 9 illustrates an example of a MIH layerwithout the MIH CS, whereas FIGS. 10-12 illustrate examples of a MIHlayer with the MIH CS. A device manager and a policy handover controlfunction of FIGS. 9-12 represent conceptual entities and as such, thefunctions of the two entities can be combined as one in a managemententity. Here, an entity can also be referred to as a module.

In the examples of the present invention to follow, the functions of thedevice manager and the policy handover control function can be carriedout by the management entity, and reference to the management entitysignifies the management entity having the functions of the twoaforementioned entities. In addition, if a mobility management protocolentity is able to perform the policy handover control function, themobility management protocol entity can carry out the managementfunctions.

FIG. 9 illustrates an architecture for implementing a protocol stack ina multi-mode mobile terminal which does not include a MIH CS inaccordance with an embodiment of the present invention. In FIG. 9,because lower MIHs communicate with upper protocols, respectively,communications from the MIHs are preferably performed via thecorresponding upper protocol or management entity.

FIG. 10 illustrates an architecture for implementing a protocol stack ina multi-mode mobile terminal which includes an MIH CS in accordance withone embodiment of the present invention. In FIG. 10, the MIH CS canmanage lower MIHs. The signals delivered from the lower MIHs can becollected by the MIH CS. The MIH CS can then transfer the collectedsignal to higher layers. Although it is possible for the MIH CS todeliver the lower layer signals to the higher layers transparently, itis preferable that the MIH CS unify the signals from the lower MIHs byvarying the lower layer signals and then deliver the unified signals tothe higher layers.

FIG. 11 illustrates an architecture for implementing a protocol stack ina multi-mode mobile terminal which includes an upper MIH CS and a lowerMIH CS in accordance with one embodiment of the present invention. InFIG. 11, an MIH is divided into an MIH Higher CS and an MIH Lower CS.Preferably, the MIH Lower CS functions similar to the MIH CS describedin FIG. 10. Similarly, the MIH Higher CS takes charge of communicationsto and from higher protocols. If necessary, the MIH Higher CS canestablish an individual SAP with each higher entity to individuallycommunicate with the respective higher entity.

FIG. 12 illustrates an architecture for implementing a protocol stack ina multi-mode mobile terminal, wherein an MIH CS exists as a function inaccordance with one embodiment of the present invention. In FIG. 12, anSAP between the MIH CS and the MIH need not exist.

Provided below are messages defined or amended in accordance with theembodiments of the present invention.

A MGMT_PowerOn.request message can be transmitted from the uppermanagement entity to the MIH. This message includes a request to theupper management entity to power on a specified link and to perform linkdetection and scanning operations. If the MIH CS exists, a list of thelinks to be detected and scanned is sent to the MIH CS.

A MIH_PowerOn.request message can be transmitted from the MIH CS to aspecified link of the MIH. This message includes a request to commencedetection and scanning operations on specified links requested by themanagement entity.

A MLME-POWERMGT.request message can be used to manage power status in amobile terminal, which accesses a wireless LAN system, and can betransmitted from a Station Management Entity (SME) to a MAC LayerManagement Entity (MLME). If a “Power On” parameter is included in themessage transmitted by the MIH of the wireless LAN (e.g., IEEE 802.11),the management entity of the MAC layer and the physical (PHY) layerpowers on the corresponding link and performs link detection andscanning operations. Alternatively, if a “Power Down” parameter isincluded in the message transmitted by the MIH of the wireless LAN, themanagement entity of the MAC layer and the PHY layer powers down/off andenters power saving mode.

A CPHY-RL-PowerOn-REQ message can be used to manage power status of themobile terminal accessing a cellular system. If a “Power On” parameteris included in the message transmitted by the MIH of the cellular system(e.g., 3GPP), the management entity of the MAC layer and the physical(PHY) layer powers on or activates the corresponding link and performslink detection and scanning operations.

A CPHY-RL-PowerDown-REQ message can be used to manage power status ofthe mobile terminal accessing a cellular system. If a “Power Down”parameter is included in the message transmitted by the MIH of thecellular system (e.g., 3GPP), the management entity of the MAC layer andthe physical (PHY) layer powers off (deactivates) and enters powersaving mode.

A CPHY-Measurement-IND message can be used to notify the upper entitiesof measured link quality results by the mobile terminal accessing acellular system. In the embodiments of the present invention, the MIHlayer or the MIH entity of the upper entities can be included.

A M_Scanning.confirmation message can be used to notify the upperentities of measured link quality results in a wireless broadbandsystem.

A MLME-SCAN.confirmation message can be used to notify the upperentities of measured link quality results by the mobile terminalaccessing a wireless LAN system.

A MIH_SCAN.confirmation message can be used by the MIH of each link tonotify measured link quality results of the received links to the MIHCS.

A MGMT_SetupLink.request message can be used by the upper managemententity to transmit information to the MIH for establishing connectionwith at least one available link or with all available links. When alist of at least two available links is transmitted, the MIH considersthe priority based on some policy in establishing a link.

A MIH_SetupLink.indication message can be used by the upper managemententity to transmit information for establishing link with at least onelink received in the MGMT_SetupLink.request message to a specific linkof the MIH.

A MIH_LinkOn.indication message can be used to notify that the MIH ofeach link has completed link establishment with the MIH CS when amessage indicating link establishment with each link is transmitted tothe MIH. This information included in the message if a mobilitymanagement protocol that can be used in the link establishment procedureis determined.

A MGMT_PowerDown.request message can include a request by the uppermanagement entity to power down for controlling power of a multi-modemobile terminal. This message can be transmitted to the MIH of thecorresponding link when the upper management entity decides to powerdown/off link(s) other than the specified link or to power down the linkfor a different reason. If the upper management entity has decided topower down more than two links, then the corresponding links can beincluded in a single message.

A MIH_PowerDown.request message can include request by a MIH CS to powerdown/off by the MIH of the corresponding link, which has been selectedby the upper management entity to power down/off. This message can betransmitted to all corresponding links selected by the upper managemententity to have the links power down/off.

A MIH_LinkOn.indication message can be transmitted to the MIH CS whenthe MIH of each corresponding link is notified by a Medium AccessControl (MAC) layer that link establishment has completed.

A Link Available message can be used by the MIH CS, after receiving alink quality measurement result of the received links, to notify theupper management entity of the available links. A list of the availablelinks can be transmitted in a single message.

A Link On message can be used by the MIH CS, after receiving that linkestablishment is completed from the MIH of the corresponding links, tonotify the upper layers including the upper management entity and themobility management entity that link is established with thecorresponding links. If connections are established with multiple links,a list of the multiple links having established connection can beincluded in the message.

A MGMT_PowerOn.confirmation message can be transmitted by the MIH to theupper management entity which manages the multi-mode mobile terminal.This message can be used by the upper management entity to transmitinformation on whether the request to power on the corresponding link inorder to perform link detection and scanning operations has beensuccessfully performed or not. If the operation is unsuccessful, thereason for the failed attempt can be included in this message.

A MIH_PowerOn.confirmation message can be transmitted by the MIH of aspecific link to the MIH CS. This message can be used by the MIH tonotify the MIH CS whether the request to power on the corresponding linkin order to perform link detection and scanning operations has beensuccessfully performed or not. If the operation is unsuccessful, thereason for the failed attempt can be included in this message.

A MGMT_PowerDown.confirmation message can be transmitted by the MIH tothe upper management entity which manages the multi-mode mobileterminal. This message can be used by the upper management entity totransmit the result of whether the corresponding link has been poweredoff/down or not, and if the power down was unsuccessful, then the reasonfor failed power off attempt can be include the message. If there aretwo or more links to power down and the result of the MIHs of more thantwo of different power down/off types is received, then all theseinformation can be included in the message and transmitted to the uppermanagement entity.

A MIH_PowerDown.confirmation message can be transmitted by the MIH tothe MIH CS. This message includes information on whether thecorresponding link has been successfully powered down or powered off. Ifthe operation is unsuccessful, the reason for the failed attempt can beincluded in this message.

In the messages above, powering on can be referred to activating thelink to allow link setup/establishment. On the contrary, poweringdown/off can be referred to as deactivating the link to allow the linkto sever the connection.

FIG. 13 is a flowchart of a procedure for initializing according toanother embodiment of the present invention. In FIG. 13, the operationof the multi-mode mobile terminal commences in order to initialize(S131). The commencement of the mobile terminal includes initial bootingup of all the interfaces and detection of available links. Initialbooting up indicates powering on the corresponding interface and oncethis powering on stage is completed, then the mobile terminal can detectand is ready to access available wired and/or wireless links (S132).

Once power to all modes is verified and ready for link detection, themobile terminal then detects for available links (S133). When anavailable link is detected, the mobile terminal selects a link toestablish connection with (S134). Since the mobile terminal ismulti-modal, more than two available links can be detected such aswireless LAN link, broadband wireless access link, wired LAN link, 3GPPcellular wireless network link and a like. If the link is selected basedon policy, a pre-selected policy with a service provider or a policyreceived dynamically by the network can be applied. Moreover, there canbe multiple link establishments.

With respect to the link establishment, Layer 2 links or below the MAClayer links can be established (S135). Here, Layer 2 includes wirelessor wired physical link. In establishing below Layer 2 links, if multiplelinks establishments are available, one link can be selected and/or allavailable or multiple links can be selected. By establishing either asingle link or multiple links, link set up can be completed (S136). Byperforming a Layer 3 link establishment procedure for communicatingInternet Protocol (IP) packets (S137), Layer 3 link can be established(S138). When the Layer 3 link establishment is completed, the multi-modemobile terminal can transmit/receive IP packets via the selected orestablished link (S139).

Hereafter, a procedure for establishing initial connection and linkestablishment of a multi-mode mobile terminal that supports a pluralityof wired or wireless interface according to preferable embodiments ofthe present invention will be described. Preferably, the multi-modemobile terminals as described in the embodiments include a mobileterminal, represented by an interface between at least two networks,from cellular networks such as wireless network, broadband wirelessnetwork, and 3GPP. Moreover, the multi-mode mobile terminals includedifferent wired LAN and different wireless LAN, preferably. Furthermore,although the wireless LAN according to the embodiment of the presentinvention describes an embodiment of a network using IEEE 802.11standard, an embodiment of a network using IEEE 802.16 standard, and anembodiment of a network using 3GPP standard, if the MIH layer is appliedto the multi-mode mobile terminal, the wireless can be applied todifferent standards as well.

FIG. 14 is a flowchart of a procedure according to an embodiment of thepresent invention. In FIG. 14, the upper management entity powers on tosetup the corresponding link (i.e., interface) of the multi-mode mobileterminal when power to the multi-mode mobile terminal is granted,detects for available links, and sends a command (i.e.,MGMT_PowerUp.request) message to the MIH CS (S141). Here, the uppermanagement entity determines an interface to connect with according toany information or policy and thereafter, can connect that particularinterface. Moreover, the upper management entity can include a list ofinterfaces with which connection can be established in theMGMT_PowerUp.request message.

The MIH CS learns of the link (i.e., interface) to establish connectionwith through the received MGMT_PowerUp.request message. According to theembodiment of FIG. 14, the MIH CS communicates directly via the MAClayer and the PHY layer of the wireless LAN interface of IEEE 802.11 orindirectly via the management entity, and transmits a message commandingthe MIH of the wireless LAN interface to power on and detect links andperform scanning to measure signal qualities (S142). The aboveembodiment is not limited to IEEE 802.11 but can also be applied to IEEE802.16, 3GPP, and/or other wired or wireless network interfaces.

As described above, the MIH of the wireless LAN interface, whichoperates while communicating directly with MAC layer and the PHY layerof the wireless interfaces or indirectly through the management entity,uses the primitives used to communicate with the management entity ofthe wireless LAN to command detection of wireless LAN links and scanningof the links to measure signal qualities (S143).

Similar to S142, the MIH CS communicates directly with MAC layer and thePHY layer of a broadband wireless access network interface of IEEE802.16 or indirectly with the management entity of the broadbandwireless access network interface of IEEE 802.16. Furthermore, the MIHCS commands the broadband wireless access network interface to power onand perform link detection and scanning procedure for measuring signalqualities (S144).

In addition, the MIH of the broadband wireless access system, whichoperates while communicating directly with MAC layer and the PHY layerof the wireless interfaces or indirectly through the management entity,uses the primitives used to communicate with the management entity ofthe broadband wireless access system to command detection of broadbandwireless access system links and scanning of the links to measure signalqualities (S145).

Further, the MIH CS of the 3GPP cellular network interface, whichoperates while communicating directly with MAC layer and the PHY layerof the cellular network interfaces or indirectly through the managemententity, commands the MIH of the cellular network to power on and performlink detection and scanning procedure to measure signal qualities(S146).

Furthermore, the MIH of the 3GPP cellular network interface, whichoperates while communicating directly with MAC layer and the PHY layerof the cellular network interfaces or indirectly with the managemententity, uses the primitives used to communicate with the managemententity of the cellular network interface to command performance of linkdetection of the cellular system and of scanning procedure to measuresignal qualities (S147).

Steps S142, S144, and S146 can be performed simultaneously. These stepsare different examples of link detection and signal quality measurementperformed by each of different interfaces (S148).

The MAC layer of the cellular system can use the primitives used tocommunicate with the management entity of the cellular network to sendthe results of the link detection and scanning to the MIH of thecellular system (S149). If the quality of the link is difficult tomeasure, the MAC layer of the cellular system can include only the linkdetection result in the primitive. Although the present embodiment isdescribed with respect to the 3GPP cellular network interface, the sameprocedure, as described above with respect to the 3GPP cellular networkinterface, can be applied to IEEE 802.11 wired LAN network and IEEE thebroadband wireless access network interface of IEEE 802.16. That is, thelink detection and scanning results can be delivered to the MIH of theeach system as done in the 3GPP cellular network interface. The MIH ofthe cellular system can transmit the results of the link detection andscanning to the MIH CS (S150).

The MAC layer of the broadband wireless network can use the primitivesused to communicate with the management entity of the broadband wirelessnetwork to send the results of the link detection and scanning to theMIH of the broadband wireless network interface (S151). If the qualityof the link is difficult to measure, the MAC layer of the broadbandwireless network can include only the link detection result in theprimitive. The MIH of the broadband wireless network can transmit theresults of the link detection and scanning to the MIH CS (S152).

The MAC layer of the wireless LAN network of IEEE 802.11 can use theprimitives used to communicate with the management entity of thewireless LAN network to send the results of the link detection andscanning to the MIH of the wireless LAN network interface (S153). If thequality of the link is difficult to measure, the MAC layer of thewireless LAN network can include only the link detection result in theprimitive. The MIH of the wireless LAN network can transmit the resultsof the link detection and scanning to the MIH CS (S154).

Thereafter, the MIH CS can notify to the management entities theavailable links based on the collected results (S155). If there is morethan one available link, the available link(s) can be organized andtransmitted in a form of a list. Here, the upper management entitycomprises the device manager, the policy handover control function, themobility management entity and a like. As illustrated in FIG. 14, if theupper management entity is classified into a manager which includes themobility management entities (e.g., MM1, MM2, MM3), the device manager,and the policy handover control function, a separate message can be sentto the mobility management entity.

The upper management entity can select a link based on the information(e.g., list of available links) received from the MIH CS (S156). Thelink selection can be based on policy and more than one link can beselected. If multiple links are selected, the selected links can beassigned priority so that multiple link establishment can be commandedat a later time.

Thereafter, the upper management entity transmits theMGMT_SetupLink.request message to the MIH CS to command linkestablishment with the selected link (S157). Here, if more than one linkhas been selected during the link selection process, then theMGMT_SetupLink.request message can include a list of the selected links.This embodiment relates to a broadband wireless access network linksselected based on some policy or situation.

After receiving the command message to establish link or setup link, theMIH CS determines the types of links received via the message from theupper management entity, and then requests link establishment with thecorresponding link (S158). In this example, the upper management entityhas selected the link from the broadband wireless access network andaccordingly, the MIH CS requests for link establishment to the MIHentity of the broadband wireless access network.

The MIH, which operates while communicating directly with MAC layer andthe PHY layer of the corresponding link or indirectly through themanagement entity, uses the primitives used to communicate with theupper management entity to command link establishment (S159). In thisembodiment, the command to establish/setup broadband wireless accessnetwork link is included in the primitive that can be used in thebroadband wireless access network.

After receiving the command message, the MAC layer and the PHY layer ofthe corresponding link establishes the link (S160). The managemententity of the corresponding link can use the primitive used by the MIHof the corresponding link and management entity to deliver the resultsof the link establishment (link setup) to the MIH of the correspondinglink (S161). The embodiment of the present invention relates to themanagement entity of the broadband wireless access system notifying theresults of the link establishment to the MIH of the corresponding link.If the mobility management protocol is negotiated or notified during thelink setup procedure, the negotiated and/or notified information can beincluded in the message sent to the MIH of the corresponding link. TheMIH of the corresponding link delivers the results of the link setup tothe MIH CS (S162). The results of the link setup can be sent even afteravailable mobility management protocol is received.

In order to notify that the upper layer can transmit packet(s) after thelink is established, the MIH CS can send a ‘Link Up’ message to theupper management entity (S163). In the message sent to the uppermanagement entity, the available mobility management protocol type(s)can be included. Furthermore, the MIH CS can send the ‘Link Up’ messageto the mobility management entity (i.e., MM1) directly to notify thatthe link has been set up (S164). Preferably, as an alternate method, theupper management entity can send the ‘Link Up’ message to the mobilitymanagement entity to notify that the link has been set up.

The mobility management entity can perform Layer 3 link set up (S165).The upper management entity can power off (deactivate) unused links inorder to conserve power consumption. In the embodiment according to FIG.14, the upper management entity can send a command to the MIH CS topower off the links connecting the wireless network and the cellularnetwork (S166). If there is more than one link whose power should bepowered down/off, then the message can include a list of these links.

The MIH CS can acquire information of the links whose power should bepowered off from the received message and transmits a request message tothe MIH of the corresponding link(s) to power off (S167, S168). Afterreceiving the power down/off message from the MIH CS, the MIH of thecorresponding link(s) can use the primitives to command power down tothe MAC layer and the PHY layer of the corresponding link(s) (S169,S170).

FIG. 15 is a flowchart of a procedure according to another embodiment ofthe present invention. In FIG. 15, the object is same as that of FIG. 14or illustrates a situation where MIH CS is not available. The embodimentof FIG. 15 is divided into two schemes, namely, Scheme 1 and Scheme 2.In detail, Scheme 1 relates to handover between heterogeneous networksaccording to the communication between the upper management entity andthe MIH. In addition, Scheme 2 relates to handover between theheterogeneous networks according to direct communication by the uppermanagement entity to the corresponding link. Here, Scheme 1 and Scheme 2seek to accomplish the same objective, and the procedures/operations ofthese two schemes can be combined and used interchangeably.

In Scheme 1, the upper management entity of the multi-mode mobileterminal can command the MIH, which communicates with a specific link,to power on to perform initial link set up (S171, S173, S175). In thisembodiment, the messages can be sent to the MIH layer which communicateswith the protocols of each IEEE 802.11 wireless LAN network, IEEE 802.16broadband wireless access network, and 3GPP cellular network. The MIH ofthe corresponding link can use the primitives used to communicate withthe management entity of the corresponding links to send a command tothe MAC layers of the corresponding links to power on to initialize linkset up (S172, S174, S176). The primitives of the steps S172, S174, andS176 can include the parameter for powering on and initializing link setup or establishment.

In Scheme 2, the upper management entity sends directly, without goingthrough the MIH of the corresponding links, a message to the MAC layerof the corresponding links where the message includes the primitive,which includes a parameter representing a command to power on andinitialize link set up, used by the management entity of thecorresponding links (S177, S178, S179).

After receiving a command to power on and initialize link set up, theMAC layer of the corresponding links can perform link set up(establishment) with the PHY layer and scanning to measure linkqualities (S180). This procedure is same in Scheme 1 and Scheme 2.

In Scheme 1, the MAC layer of the each interface delivers the primitiveswhich includes the results of the link detection and link qualitymeasurement (i.e., scanning) to the MIH layer of each corresponding link(S181, S183, S185). Here, if the link was not detected in the MAC layerof the interface, this primitive would not be sent. Thereafter, the MIHof each corresponding link delivers the received results of the linkdetection and link quality measurement to the upper management entity(S182, S184, S186). That is, the upper management entity is notified ofthe available links that communicate with the MIH. If the link isavailable, the quality of the link can be included in the message to theupper management entity. Although the embodiment of the presentinvention provides information related to available links in the uppermanagement entity, it is possible to provide this information to themobility management entity.

In Scheme 2, the MAC layer of the corresponding interfaces havingdetected the links delivers directly the primitives which includes theresults of the link detection and link quality measurement (i.e.,scanning) to the upper management entity (S187, S188, S189).

After receiving the results, the upper management entity can select alink(s) based on the results of the available link(s) (S190). Here, amultiple links can be selected according to the policy. According to theembodiment of FIG. 15, the upper management entity selects the link;however, the mobility management entity can make the link selection aswell. This selection procedure can be uniformly applied to Scheme 1 andScheme 2.

In Scheme 1, the upper management entity can request to the MIH of thecorresponding link for a link set up with the selected link (S191).Subsequently, the MIH of the corresponding link delivers the linkselection information to the MAC layer using the primitive that can beused in the corresponding interface (S192). The embodiment as shown inFIG. 15 illustrates a link setup procedure in the broadband wirelessaccess network interface.

In Scheme 2, the upper management entity can use the primitive used bythe corresponding interface to send a message to command linkestablishment with the MAC layer of the corresponding link (S193). Inthis embodiment, the upper management entity sends the request; however,it is possible for the mobility management entity to send the request aswell.

After receiving the command to establish link, the MAC layer of thecorresponding link can establish or set up link (S194). Here, it ispossible for the MIH to establish link during the link set up procedure.The step S194 can be applied in Scheme 1 and Scheme 2.

In Scheme 1, the MAC layer of the corresponding link can notify the MIHof the corresponding link that the link set up is complete (S195). Ifthe mobility management protocol to be used is determined during thelink set up procedure, then this mobility management protocolinformation can be included in the notification tot the MIH of thecorresponding link. Thereafter, the MIH can notify the mobilitymanagement entity that the corresponding link has established link(S196). Here, the mobility management entity receiving the linkestablishment information is the mobility management entity determinedduring the link set up (or establishment) procedure. In addition, theMIH can deliver link set up complete message to the upper managemententity (S197). Here, the message can include the information of themobility management entity to be used.

In Scheme 2, the MAC layer of the corresponding link can directly notifyto the upper management entity and the mobility management entity thatlink set up is completed by using the primitive used by thecorresponding link (S198, S199)

After being notified that link is established with the entities belowLayer 2, the mobility management entity can set up links in Layer 3(S200). This procedure can be applied in Scheme 1 and Scheme 2.

In Scheme 1, the upper management entity can send a message requestingpower off (deactivation) of the links (e.g., wired LAN network of IEEE802.11, cellular network of 3GPP), other than the selected link, to theMIH of the corresponding link (S201, S203). In operation, the MIH of thecorresponding link can use the primitive to send a power off request tothe MAC layer via the upper management of the corresponding link (S202,S204).

In Scheme 2, the upper management entity can directly send a message tothe MAC layer of the corresponding link to request for link powerdown/off on the links other than the selected link (S205, S206).

FIG. 16 is a flowchart of a procedure according to another embodiment ofthe present invention. More specifically, FIG. 16 illustrates aprocedure for setting up multiple links. That is, a multiple link setups can be performed on the links of multiple interfaces detected by theupper management entity or the mobility management entity.

Each interface of the multi-mode mobile terminal can perform linkdetection procedure (S211). The result of the link detection can betransmitted to the MIH CS via the MIH of each link. Thereafter, the MIHCS can notify the received results of the link detection to the uppermanagement entity (S212). Here, if more than two links are detected, alist of the detected links can be sent to the upper management entityfor link selection.

When the upper management entity determines to set up multiple links, alink setup request message, including a list of at least two links, canbe sent to the MIH CS requesting for multiple link set up (S213). Here,the priority of the list of the links can be based on a policydetermined by the manager or some other policy. In the embodiment ofFIG. 16, the 3GPP cellular network has the highest priority, followed bythe wireless LAN network of IEEE 802.11 and the broadband wirelessaccess network of IEEE 802.16. This order of priority is merely anexample and can be arranged in different order.

After receiving the link setup request message, the MIH CS can send amessage commanding the MIH of the corresponding link (interface) tocarry out the link set up in the order provided in the message (S214).That is, the command message instructs the link set up with the cellularlink having the highest priority first. Thereafter, the MIH of thecellular interface and the entities below the MAC layer (also referredto as MAC sublayer), including the MAC layer, can perform the link setup procedure (S215). If the link set up procedure fails (S216), amessage need not be sent or a message indicating link set up failure canbe sent to the MIH so that the failure message can be relayed to the MIHCS.

The MIH CS can determine whether the link set up is successful or notbased on a timer or the failure message relayed from the MIH. Afterdetermining the failed outcome of the link set up procedure, the MIH CScan proceed to set up link with the link having the next highestpriority. In the present embodiment, the link set up is commanded with alink having the next highest priority, which is the wireless LAN link,based on a timer after a specified time elapses (S217). The MIH of thewireless LAN interface and the entities below the MAC layer, includingthe MAC layer, can perform the link set up procedure (S218). If the linkset up with the wireless LAN network fails (S219), the MIH CS candetermine failed link set up based on the timer or the link set upfailure message relayed from the MIH. After determining the failedoutcome of the link set up procedure, the MIH CS can proceed to set uplink with the link having the next highest priority. In FIG. 16, the MIHCS requests a link set up with the link having the next highestpriority, that being the broadband wireless access network (S220).

Subsequently, the MIH of the broadband wireless access network and theentities below the MAC layer, including the MAC layer, can carry out thelink set up procedure (S221). If the link set up is successful, amessage indicating a successful link establishment can be sent to theMIH CS (S222). Then, the MIH CS relays the message of the successfullink set up to the upper management entity (S223). Here, the informationof the established link can be included in the message. Furthermore, theMIH CS can notify the message of the successful link establishment tothe mobility management entity (S224). Here, the information of theestablished link can be included in the message.

FIG. 17 is a flowchart of a procedure according to yet anotherembodiment of the present invention. More specifically, FIG. 17illustrates a procedure in which the MIH CS performs link set upprocedure sequentially. That is, when multiple links are successfullyset up, the MIH CS can select the link based on the priority receivedfrom the upper management entity.

Each interface of the multi-mode mobile terminal can perform linkdetection procedure (S231). The result of the link detection can betransmitted to the MIH CS via the MIH of each link. Thereafter, the MIHCS can notify the received results of the link detection to the uppermanagement entity (S232). Here, if more than two links are detected, alist of the detected links can be sent to the upper management entityfor link selection.

When the upper management entity determines to set up multiple links, alink setup request message, including a list of at least two links, canbe sent to the MIH CS requesting for multiple link set up (S233). Here,the priority of the list of the links can be based on a policydetermined by the manager or some other policy. In the embodiment ofFIG. 17, the 3GPP cellular network has the highest priority, followed bythe wireless LAN network of IEEE 802.11 and the broadband wirelessaccess network of IEEE 802.16. This order of priority is merely anexample and can be arranged in different order.

After receiving the link setup request message, the MIH CS can carry outthe link set up procedures sequentially the links in the order providedin the message. That is, the MIH CS can send a message commanding theMIH of each interface to carry out link set up (S234, S235, S236).Thereafter, the MIH of each link can communicate with the entities belowthe MAC layer, including the MAC layer, and can carry out the link setupprocedure (S237).

If the link set up is successful, the MIH of each link can send amessage to the MIH CS notifying that the link set up is successful(S238, S239, S240). Preferably, the message sent to the MIH CS includesthe mobility management protocol determined during the link setupprocedure. The steps S238, S239, and S240 do not represent the order inwhich the link set up is performed, but the steps are performedsequentially. As such, the messages are sent in order of successful linkset up.

More specifically, the MIH of the broadband wireless access network cansend a message to the MIH CS to notify that the broadband wirelessaccess network is successfully linked (S238). Similarly, the MIH of thecellular network can notify the MIH CS that the link has beensuccessfully established (S239). Moreover, the MIH of the wireless LANnetwork can send a message to the MIH CS notifying that the wireless LANnetwork is successfully linked (S240).

The MIH CS can select one established link from a plurality ofsuccessfully established links according to the priority preference sentfrom the upper management entity during the link setup procedure wasbeing carried out (S241). Here, the link selection can be based on thepriority transmitted from the upper management entity or based onservice durability according to the types of mobility managemententities determined during the link set up procedure. In FIG. 17, thecellular network has the highest priority and therefore, the link isestablished with the cellular network.

The MIH CS can then notify to the upper management entity that link setup procedure is completed (S242). Furthermore, the MIH CS can alsonotify that the link set up procedure is completed to the mobilitymanagement entity (S243).

FIG. 18 is a flowchart of a procedure according to another embodiment ofthe present invention. More specifically, FIG. 18 illustrates aprocedure in which the link set up procedure performed sequentially bythe MIH CS is unsuccessful.

Each interface of the multi-mode mobile terminal can perform linkdetection procedure (S251). The result of the link detection can betransmitted to the MIH CS via the MIH of each link. Thereafter, the MIHCS can notify the received results of the link detection to the uppermanagement entity (S252). Here, if more than two links are detected, alist of the detected links can be sent to the upper management entityfor link selection.

When the upper management entity determines to set up multiple links, alink setup request message, including a list of at least two links, canbe sent to the MIH CS requesting for multiple link set up (S253). Here,the priority of the list of the links can be based on a policydetermined by the manager or some other policy. In the embodiment ofFIG. 18, the 3GPP cellular network has the highest priority, followed bythe wireless LAN network of IEEE 802.11 and the broadband wirelessaccess network of IEEE 802.16. This order of priority is merely anexample and can be arranged in different order.

After receiving the link setup request message, the MIH CS can carry outthe link set up procedures sequentially the links in the order providedin the message. That is, the MIH CS can send a request message to theMIH of each link interface requesting for link set up sequentiallywithout order preference (S254, S255, S256). In detail, the step S254relates to the MIH CS making a request to the MIH of the cellularnetwork for a link set up with the cellular network. The step S255relates to the MIH CS making a request to the MIH of the wireless LANnetwork for a link set up with the wireless LAN network. The step S256relates to the MIH CS making a request to the MIH of the broadbandwireless access network for a link set up with the wireless broadbandwireless access network.

The MIH of each link can communicate with the entities below the MAClayer, including the MAC layer, and performs the link set up procedure(S257). In the embodiment of FIG. 18, the link set up procedures of thewireless LAN network and the cellular network fails during the link setup procedure of each link (S258, S259) while the link set up procedureof the broadband wireless access network succeeds (S260). Whether thelink set up is successful or not can be determined based on the elapsedtime using the timer by the MIH CS or based on a message notifying theoutcome of the link set up procedure via the MIH of the wireless LANnetwork.

The MAC layer of the broadband wireless access network can notify theMIH layer of the broadband wireless access network of the successfullink set up (S261). Thereafter, the MIH of the broadband wireless accessnetwork can notify the MIH CS of the successful link set up (S262). TheMIH CS then notifies the upper management entity that the link set upwith the broadband wireless access network is successful (S263). Lastly,the MIH CS can also notify the mobility management entity of thesuccessful link set up of the broadband wireless access network (S264).

FIG. 19 is a flowchart of a procedure according to another embodiment ofthe present invention. More specifically, FIG. 19 illustrates aprocedure for link selection according to a policy when the link set upfails.

Each interface of the multi-mode mobile terminal can perform linkdetection procedure (S271). The result of the link detection can betransmitted to the MIH CS via the MIH of each link. Thereafter, the MIHCS can notify the received results of the link detection to the uppermanagement entity (S272). Here, if more than two links are detected, alist of the detected links can be sent to the upper management entityfor link selection.

When the upper management entity determines to set up multiple links, alink setup request message, including a list of at least two links, canbe sent to the MIH CS requesting for multiple link set up (S273). Here,the priority of the list of the links can be based on a policydetermined by the manager or some other policy. In the embodiment ofFIG. 19, the 3GPP cellular network has the highest priority, followed bythe wireless LAN network of IEEE 802.11 and the broadband wirelessaccess network of IEEE 802.16. This order of priority is merely anexample and can be arranged in different order.

After receiving the link setup request message, the MIH CS can carry outthe link set up procedures sequentially the links in the order providedin the message. That is, without preference to the order, the MIH CS cansend a request message to the MIH of the cellular network to request forlink set up with the cellular network (S274), to the MIH of the wirelessLAN network to request for link set up with the wireless LAN network(S275), and to the MIH of the broadband wireless access network torequest for link set up with the broadband wireless access network(S276).

The MIH of each link can communicate with each entity below the MAClayer, including the MAC layer, and performs the link set up procedure(S257). In the embodiment of FIG. 19, the result of the link set up withthe cellular network is a failure (S278), but the link set up withwireless LAN network and the broadband wireless access network issuccessful (S279, S280). Whether the link set up is successful or notcan be determined based on the elapsed time using the timer by the MIHCS or based on a message notifying the outcome of the link set upprocedure via the MIH of the wireless LAN network.

The MAC layer of the broadband wireless access network can notify theMIH layer of the broadband wireless access network of the successfullink set up (S281). Thereafter, the MIH of the broadband wireless accessnetwork can notify the MIH CS of the successful link set up (S282).

The MAC layer of the wireless LAN network can notify the MIH layer ofthe wireless LAN network of the successful link set up (S283).Thereafter, the MIH of the wireless LAN network can notify the MIH CS ofthe successful link set up (S282).

The MIH CS can select a link from the notified link established links(S285). Here, the link selection can be based on the prioritytransmitted from the upper management entity or based on servicedurability according to the types of mobility management entitiesdetermined during the link set up procedure. In FIG. 19, the wirelessLAN network is given the highest priority by the upper management entityand is therefore selected.

The MIH CS can then notify to the upper management entity that link setup procedure is completed (S286). Furthermore, the MIH CS can alsonotify that the link set up procedure is completed to the mobilitymanagement entity (S287).

It will be apparent to those skilled in the art that variousmodifications and variations can be made in the present inventionwithout departing from the spirit or scope of the inventions. Thus, itis intended that the present invention covers the modifications andvariations of this invention provided they come within the scope of theappended claims and their equivalents.

1. A method of managing power in a multi-mode mobile terminal capable ofperforming a handover to at least one of a homogeneous and heterogeneousnetwork, the method comprising: receiving a first message from an upperlayer module of the multi-mode mobile terminal to command power down ata media independent handover (MIH) module, wherein the first messageindicates a specified link to be powered down, and wherein the MIHmodule is configured to converge information received from at least onenetwork interface module of the multi-mode mobile terminal correspondingto the at least one of a homogeneous and heterogeneous network into aunified presentation to be provided to the upper layer module; sending asecond message to power down the specified link to one of the at leastone network interface module, wherein the one of the at least onenetwork interface module corresponds to the specified link; performing apowering down operation on the one of the at least one network interfacemodule corresponding to the specified link; and transmitting aconfirmation message from the one of the at least one network interfacemodule corresponding to the specified link for indicating a status ofthe powering down operation to the MIH module.
 2. A method of managingpower in a multi-mode mobile terminal capable of performing a handoverto at least one of a homogeneous and heterogeneous network, the methodcomprising: receiving a first message from an upper layer module of themulti-mode mobile terminal to command power down at a media independenthandover (MIH) module, wherein the first message indicates a specifiedlink to be powered down, and wherein the MIH module is configured toconverge information received from at least one network interface moduleof the multi-mode mobile terminal corresponding to the at least one of ahomogeneous and heterogeneous network into a unified presentation to beprovided to the upper layer module; transmitting a second message forpowering down the specified link, wherein the second message istransmitted from the MIH module to the at least one network interfacemodule; and receiving a confirmation message in the MIH module forindicating a status of a powering down operation from the at least onenetwork interface module.
 3. The method of claim 1, wherein thespecified link is selected among at least one non-established link. 4.The method of claim 1, wherein performing the powering down operationincludes deactivating the network interface module associated with thespecified link.
 5. The method of claim 1, wherein the status comprisesinformation related to results of powering down the specified link. 6.The method of claim 1, wherein the MIH module communicates with the atleast one network interface module through one of a MAC sublayermanagement entity and a network control management system.
 7. The methodof claim 6, wherein the network control management system supports amanagement function of the multi-mode mobile terminal and is a layer inan independent management entity.
 8. The method of claim 6, wherein theMAC sublayer management entity is included in the MAC layer and provideslayer management service interfaces through which layer managementfunctions is invoked.
 9. The method of claim 1, wherein the at least onenetwork interface module comprises at least one of a wireless local areanetwork interface module and a wireless metropolitan area networkinterface module.
 10. The method of claim 1, wherein the at least onenetwork interface module comprises at least one of a WCDMA interfacemodule and a cdma2000 interface module.
 11. The method of claim 1,wherein the MIH module communicates with the at least one networkinterface module through a management service access point and a controlservice access point.
 12. The method of claim 1, wherein the MIH modulecommunicates with the at least one network interface module through oneof a MAC sublayer management entity and a physical layer managemententity.
 13. The method of claim 1, wherein the second message includesan original primitive for the network interface module associated withthe specified network.